1. Field of the Invention
This invention relates to new and useful improvements in combustion devices for the destruction by burning of industrial and other wastes, or alternatively the combustion of high sulfur fuels such as coal or the like, and has as its overall object the provision of such a furnace capable of performing this operation cleanly and economically, providing a maximum of heat. The cyclonic effect of the furnace is especially designed to minimize the particulate matter escaping through the flue so that the material to be combusted produces a minimum amount of polluting particulate, maximizes the degree of burning of the feedstock material therein, and makes the most efficient use of the sorbent introduced into the device hereof.
2. Description of the Prior Art
A variety of furnaces and kilns have been provided in the past for combusting fuels or waste products to generate heat and/or to pyrolitically alter the feedstock material. In some cases, the furnace or kiln is provided with various air inlets in order to introduce combustion air into the kiln body in an attempt to provide ample combustion air to the site of the burning materials. The hot combustion gases are removed from the kiln through a flue, and invariably a problem is created by the entrainment and emission escape of ash or partially combusted material through the flue. In order to minimize the escape of ash to the atmosphere, it has heretofore been necessary to provide furnaces and kilns with flue gas scrubbers for cleaning the effluent and inhibiting the escape of particulate matter into the atmosphere.
Moreover, certain materials to be combusted have a tendency to generate not only ash and other particulate material as a product of combustion, but also discharge vapors which include sulfur dioxide or hydrochloric acid which, when released to the atmosphere, ultimately fall to earth, producing the undesirable phenomena called "acid rain". Obviously, such byproducts are undesirable, and when materials such as high sulfur coal are burned in a furnace, it may be desirable to introduce a sorbent to react with the sulfur in the coal. Unfortunately, prior sorbent injection systems have not been effective in suspending and distributing sorbent throughout the kiln body for maximum reaction with all of the material to be combusted.